Now that you simply mention it, the initial two tracks manage to lack reduced bass, (apart from a bass drum hit just prior to the fade out of Custard Pie). But then “In My Time of Dying” appears to have some additional bass… not sure what was taking place https://led-zeppelin-gold-record69009.bloggactif.com/27269995/the-5-second-trick-for-led-zeppelin-gold-records